Carburetor



June 19, 1934- R. voN BECKER 'ET AL CARBURETOR Filed. April 4, 1932Patented June 19, 1934 UNITED STATES In Germany Claims.

Our invention relates to improvements in spray carburetors for internalcombustion engines which have, besides the main spraying nozzle for thefuel and if necessary an idle running noz- 5 zle, also an auxiliarynozzle coordinated to the main nozzle and fed by a fuel supply pumpactuated with the throttle element. In the old arrangements the controlof the pump piston is effected positively with the adjustment of thethrottle valve by a lever fixed on the pivot axle of the throttle valveand connected at its free end with the piston or some kind of rigidlever connection between the piston and the rod system controlling thethrottle valve.

According to this invention the positive coupling between the throttleelement and the pump piston is replaced by a controlling element whichis constructed or adjusted in such a manner that it only transmits themovement of the throttle 20 valve to the pump piston in the case ofcertain predeterminable positions of the throttle Valve. Thisarrangement presents the advantage that an enriching of the mixturethrough the auxiliary nozzle only takes place whilst the throttle valveis in certain positions, By introducing a resilient element into thetransmission element, for example a spring, the fuel is forced out ofthe cylinder in a uniform jet maintained for a long time; excessivepressures are taken up by the spring and consequently damage to the pumpis avoided. An adjustable spiral spring exchangeably fixed on the pivotaxle of the throttle valve preferably serves as transmission element.The .free end of this spring bears either directly or indirectly on thepiston subjected to the action of a return spring and is of suchdimensionsthat it is relieved when the throttle valve is in certainselected positions, that is, has no influence on the piston during theadjustment of the throttle valve within a certain range. Thecommencement of the movement transmission can be determined bycorrespondingly dimensioning the return spring for the piston, and thestroke of the piston can also be limited by its thickness or by a pumpbeing chosen having small dimensions in such a manner that from acertain position of the throttle valve which can be chosen the pistoncomes to a standstill whilst the throttle valve is further 50- opened.The piston no longer follows the movements of the throttle valve sothat, when the throttle valve is adjusted behind this predeterminedpoint, no more fuel is supplied as is the case with a rigid coupling. 55Several embodiments of the invention are illusrari-:Nr OFFICE' 'i c;

CARBURETOR Reinhold von Becker, Darmstadt, Germany, and JesdimirDjordjevitch, Paris, France Application April 4, 1932, Serial No. 603,18

April 10, 1931 trated by way of example in the a drawing in whichr- YFig. 1 shows the carburetor partly in longitudi-- nal section along lineI-I in Fig. 2.

Fig. 2 is a top plan View of tion. l v

Fig. 3 is aY section along line III-III'in Fig. 2. Fig. 4 shows partlyin longitudinal Ysection a' modification. Fig. 5 shows on a larger scalethe adjustable mounting of the spring on the axle of the throt-w tlingelement, along the line V-V in Fig. f1."'v The carburetor consists ofj afloat ,chamber 1, a mixing chamber 3 with throttle valve 4 and mainnozzle 5 which communicates by a conduit Fig. i par'uy in ,se-A

ccompanying with the float chamber 1. A fuel pump 7 arranged 75,15:` Theair do not form the subject matter of the present invention beingdescribed together with their operation in detail in our copendingapplication Serial No. 603,181, filed April 4, 1932. The adjustment ofthe throttle valve 4 is effected in well known manner by an adjustinglever 14. On the end of the pivotal axle 15 of the throttle valve 4situated opposite the adjusting lever 14 an adjustable spiral spring 16is exchangeably mounted, the free end of this spring bearing against thetop of the piston 9 (Fig. 1). secured to the axle 15 by a set screw 18extending through a slot 19 at the end of the spring, thus enabling thelatter to be adjusted, as shown in Fig. 5. When the throttle valve 4 isopened the spiral spring 16 is tensioned as the piston 9 is held back bythe fuel enclosed in the cylinder. However, as soon as the tension ofthe spring 16 exceeds the counter pressure exerted by the return spring13 and the fuel the piston 9 is pressed slowly into the pump cylinder 7and supplies the fuel through the auxiliary nozzle 11 in a uniform jetwhich is maintained for a long time. If the throttle valve 4 is returnedto its closing position, the spring 16 is relieved, so that the piston 9will be pushed by the return spring 13 into'. its initial position andthe fuel supply of the pump will be interrupted during the adjustment ofthe throttle valve. According to the strength of the springs 16 and 13the spiral spring 16 is lifted .9031: i The Spring 16 is 95h lfQO;

2 from the ypiston 9.When the throttle valve 4 is in its closingposition, the stroke of the piston being limited by an abutment `20(Fig. 4) and only commences to force the piston 9 in to the cylinderwhen the throttlevalve 4 has reached a certain 'Y position or it remainsbearing on the piston 9 (Fig. l) In both linstances the piston 9 is onlyshifted towards its ,lower dead` `centre position when the tensionofthespring 16 exceedsv the pressure exerted bythe return spring 13.

'I'he device vaccording to the invention may be.4 arranged on all pumpsystems for carburetors'ad is'not limited to the embodiments hereind'eaLscribed or shownon the appeifideddrawing.l

Weclaim:l

1. In a spray carburetor 'controlledbyathrot-` tle valve having apivotal axle, in combination with 'said throttle valvega'nditspivotalaxle, Ya fuel feeding device, comprising a fuel pump,.'a pistontherein, and a spiral spring on said' axle having a-free end adapted toyoperate said piston with its free end.

v2. In a spray carburetor controlled by a throttle valve having apivotal axle, in combination :zwith said throttle valve and'its pivotalaxle, a

fuel feeding device, comprising a fuel pump, a piston therein, andanexchangeable spiral spring adjustably mounted on said a'xle having afree end and adapted to operate said piston with its free 3. .In a spraycarburetor controlled bya throttle valve having a pivotal axle, in4combination Withfsaid throttle valve and its` .pivotal axle, a

fuel feeding device, comprisingA a fuel pump, a piston therein, anexchangeable spiral spring adjustablyw mounted on said axle having afree end and adapted to operate said piston With its free end, and anabutment' for limiting the upward stroke of said piston.

4. In a spray carburetor controlled by a throttle valve having apivotalaxle, in combination With said throttle valve'and its pivotal axle, afuel feed-device, comprising a fuel pump, a piston thereiiua returnspring adapted toy act on said piston, an exchangeable'sp'iral springladjustably mounted onl said 'axle having a free endl and adapted tobearwith.. its free end on said piston, the tensional .strength 'of lsaidspring when said throttle valve is in closing position being always lessthan thefpressu're exerted by said return spring.' 1 l 5. In a spraycarburetor controlled by a throt- 'tle` valve havinga pivotal axle, incombination

